More particularly, the invention relates to a method for estimating the elevation change traveled by a user, by means of a device intended to be worn or carried by the user, said device being adapted to measure the ambient pressure and deduce the corresponding altitude from it. The measurement of pressure changes allows deducing the corresponding change in altitude and consequently deducing an elevation change traveled by the user.
Document US 2012084053 describes a device for monitoring and recording a user's movement, and in particular for determining elevation changes traveled by that user. However, the estimation method applied in this document uses an algorithm based on threshold filters and hysteresis mechanisms.
Such an algorithm can be skewed by one-time anomalous values that can lead to unwanted inclusion as a change, especially if the device containing the pressure sensor is subjected to the acoustic phenomena that can occur when an individual enters a room, opens a door, takes the elevator, or is in a vehicle that enters and exits a tunnel. Moreover, such an algorithm requires significant computing power and memory capacity.
There is therefore a need to provide an improved method for filtering the pressure values measured or converted into altitude values, so as to eliminate the anomalous values while providing the elevation changes traveled in near real-time, but where the method does not require too much computing power.
Throughout this application, the term “buffer” will be used to refer to buffer memory storage.